The United Kingdom generates a simple 1.1% of global emissions greenhouse gases. This makes it the 16th largest emitter. Even if all his broadcasts ceased tomorrow, the world would hardly notice. So what could be its role? The answer is, it could be both an example and a leader. He can demonstrate what top-notch politics would look like, and he can push the world on a different course before it’s too late. The first is vital. He cannot have influence in the world if he is not successful at home. So how are you?

The answer is: not good enough. Unlike mad Republicans, conservatives don’t deny the science. Progress has already been made towards decarbonization. The government has also pledged the UK to cut emissions 68% in 2030 and 78% in 2035 below 1990 levels. In addition, the 2035 target will include, for the first time, its share in international aviation and maritime transport. But neither progress nor policies are as good as they should be. If the UK is to be a role model and a leader, it must do more.

Between 1990 and 2018, UK territorial CO2 emissions have fallen by 39%. Even more impressively, they fell by 21% just between 2013 and 2018. But 63% of the reduction over the longer period, and 85% of that over the shorter period, was due to decarbonization of the energy supply alone. – mainly the elimination of coal and the growth of renewable energies. Companies have also reduced their emissions significantly. But little has happened elsewhere.

Importantly, nearly 40% of emissions for which UK residents were responsible in 2016 were outside the country. The largest of these came from net imports (34 percent of the UK’s carbon footprint), aviation (4 percent) and shipping (1 percent). The UK has the second most carbon efficient economy in the G7 group of high income countries, behind France. But it still has a long way to go to reach net zero, especially if we focus on its global footprint.

Bar chart of energy related emissions per unit of GDP (kg per USD at 2015 prices) showing The UK economy currently emits rather little per unit of economic output

What needs to be done? The good news is that the transition to net zero is doable and also much cheaper than what most feared just ten years ago. When you factor in the benefits of cleaner air, making the switch is ‘no-brainer’ for the UK only. Yet it is also complex and will require difficult choices.

In terms of sectors, the major challenges for 2035 are energy, transport and residential heating.

When it comes to energy, a set of regulations, incentives and procedures are needed to stimulate the necessary investments in a fully renewable system. It is now more or less on the right track. In transportation, too, the shift to electric vehicles may be even faster than most people currently think, as costs drop and battery efficiency continues to rise. The UK’s commitment to ban the sale of internal combustion engine cars by 2030 is significant. Its biggest omission is the failure to invest in the necessary expansion of charging infrastructure. A third of UK households do not have off-street parking. This gap needs to be filled fairly quickly.

Bar chart of air emissions (million tonnes of CO2 equivalent, 2016) showing official UK greenhouse gas emissions estimates vary widely

However, not much is happening for residential heating. The switch to heat pumps, for example, will be demanding and expensive. Many people will need financial help, especially to improve insulation.

The right incentives are as important as such sector plans, via emissions taxation and subsidizing negative emissions. A 2020 report from Zero Carbon Commission (written by my daughter) analyzed the politics and economics of carbon pricing in the UK.

Pricing emissions is a necessary but not sufficient condition to effectively achieve net zero. A price would cover all activities, make polluters pay, exploit the motive of economic gain, and encourage people to exploit their knowledge. A carbon price would also increase incomes, which could be used to help poorer households pay for the costly changes they will have to make.

The Zero Carbon Commission recommends a price of £ 75 per tonne of CO2 in 2030, which would also increase just over 1% of gross domestic product. In addition to generating revenue, a flat tax would eliminate the current differences in implicit emissions prices across the economy. Today, for example, electric heating is taxed more heavily than gas. That does not make any sense.

Line graph of air emissions (million tonnes of CO2 equivalent) showing that consumption-related emissions also decreased less than production-related emissions

Yet if the UK were to tax energy-intensive tradable activities more heavily, it would move abroad even faster. This would be politically unacceptable and it is also highly likely that it will lead to an increase in global emissions. The answer must be a border tax adjustment. It could even speed up the transition to global limits.

The UK has ambitious goals and good plans. But these also have obvious holes. Above all, he did not announce a credible tax on emissions. He has to do better if he wants to lead.

[email protected]

Follow Martin Wolf with myFT and on Twitter